The Centers for Disease Control and Prevention say herpes type 2 virus is declining in the country. A new study found a significant decrease in cases in Americans between the ages of 14 and 49.

Herpes 2 is the most common cause of genital herpes, and is one of the most common sexually transmitted diseases. The study found that the number of people who tested positive for the disease is down by 19 percent since 1994.

The number of people who tested positive for the herpes 1 virus in their blood also decreased.